Various tasks related to space navigation, such as landing on the Moon or Mars, Earth re-entry, or docking with another space craft, require very precise navigational data. This navigational data may include, for example, a range to a ground surface, a ground velocity of the space craft, or an air velocity of the space craft. Highly precise navigational data would enable spaceborne vehicles to navigate, with a high degree of precision, to an intended landing site. Additionally, the range to the ground surface measured along three or more different line-of sites would allow the determination of the vehicle attitude angles relative to the ground. Furthermore, the air velocity of the vehicle may be used to derive the vehicle's angles of attack and side slip, which may be used for guidance and control of the vehicle.